Teens are shy to talk about how much time they spend on their phones, but it's a lot.

We got lots of "too many" and "I'm embarrassed to say" responses, but the numbers we were able to get suggested teens spend about six hours a day on their phones. (This is both in and out of school.)

What are teens' favorite apps? Here are a few of the most popular answers:

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The most popular by a landslide: Snapchat.

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It's no surprise that teenagers love Snapchat. Here's what they had to say about it:

"It's how I communicate with most of my friends and it's fun." — a 15-year-old

"Snapchat because it's pretty much just texting, but with pictures of my beautiful face " — a 16-year-old

"Snapchat, because it is fun to send your friends what you're doing, and where you are in a fast and easy way. I also like being able to make stories, for all of my friends to see, and I also enjoy seeing stories of my friends on it and see what they're up to." — a 17-year-old

Spotify was almost universally heralded as the best music app, and it was also listed as a favorite app by a lot of respondents.

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Teenagers we spoke to almost universally named Spotify as their preferred music-streaming service — and some teenagers said it was the best app on their phone overall:

"I use it to share music, to see what my friends are listening to, and to find new music." — a 14-year-old

Instagram was another favorite.

Instagram is a standby favorite of teens, who swear by its filters and direct-message feature. Here's what they said:

"I use Instagram to message my friends funny pictures I see on Instagram." — a 15-year-old

"Snapchat and Instagram, I love sharing photos all of the things I do and places I go. I also like seeing what others are up to." — a 15-year-old

The dark horse: Twitter.

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You might not expect Twitter to be among teens' favorite apps. After all, the company is having a hard time attracting new users. But a lot of teenagers we talked to really liked the platform. Here what they had to say:

"Twitter because I can update everyone all the time quickly and it's not annoying like Facebook." — a 17-year-old

Twitter because "you can voice your opinion on anything you want to and you can somewhat interact with celebrities." — a 18-year-old

"My favorite app is Twitter because I am the kind of person who needs to get out my thoughts, and Twitter may be like shouting into the void but at least I am heard and often validated by my peers." — a 19-year-old

Absent from the list: Facebook.

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The teens we talked to said they and their friends were still using Facebook — but it wasn't their favorite app. Here's why:

"I use Facebook, but I feel like I can't be myself on it because my parents and my friends' parents are my Facebook friends." — a 16-year-old

"It's mostly outdated." — a 14-year-old

"Facebook is good for group events and things but it's definitely not my favorite app." — a 15-year-old

This pretty much lines up with what teens across the board are saying.

Facebook may be dead to teens, but a surprising number of them are texting their friends through Facebook Messenger.

Facebook

The most common form of messaging among teenagers in our survey was iMessage or SMS messaging — 100% of the teens we talked to used one or both of those.

But Facebook Messenger was mentioned almost as frequently — 80% of teenagers we spoke with said they used Facebook Messenger as a primary or secondary form of communicating with friends. Less popular were WhatsApp, Kik, and Snapchat text.

We also asked teens to identify the coolest app, website, or thing on the internet that adults probably didn't know about.

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We got a fair number of responses from teens who thought Twitter, Tumblr, and Snapchat were cool (and they are!) and that adults didn't know about them (but they do!).

But we found a few responses genuinely surprising.

After School.

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Several teens brought this app to our attention. We first wrote about After School, a social network created specifically for high-school students, when it launched and started gaining traction in late 2014.

If you're nervous thinking about the kinds of stuff teenagers would post anonymously on a social network, you're not alone. Millions of teens are using it to post their "deepest anxieties, secret crushes, vulgar assessments of their classmates, and even violent threats," according to The Washington Post.

Musical.ly.

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You've probably never heard of Musical.ly, but it has already cracked the top 20 in Apple's App Store. The app has quietly grown to its popular status without any press.

Musical.ly lets you make music videos of yourself or of other people. It may not seem like a particularly compelling value proposition, but 10 of the 60 teens we spoke with listed Musical.ly as the app they were most excited about and doubted adults would know about.

Color Therapy.

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Remember when you were a kid and you colored in coloring books? Color Therapy is a stress-relieving, digital coloring book for adults, and the teens we talked to swore by it.

Wishbone.

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Launched by the Los Angeles venture-capital firm Science's mobile studio, Wishbone shows you two options and lets you vote on which one you like more — a spin on the popular "Would you rather?" hypothetical question.

"Neko Atsume."

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You have probably never heard of the Japanese game "Neko Atsume," but numerous teens we talked to were obsessed with it. The game's name literally translates to "cat collecting," and that's exactly what you do in the adorable game.

"Color Switch."

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Speaking of games, a bunch of teens also mentioned "Color Switch." In this game, you must follow each color pattern you're shown on each obstacle to progress.